Townsend’s Warbler

It’s November. We are thinking turkeys, chickadees and nuthatches, our permanent fall and winter residents, as well as flocks of waxwings, redpolls and, if we are lucky, a snowy owl. But, it is also good to look forward to the splashes of color and songs of warblers that will return in the spring. One of the first arrivals is the Townsend’s Warbler (Setophaga townsendi).

This bright yellow, black, white and greenish warbler is named for John K. Townsend, an avid ornithologist who at the age of 24 joined an expedition in 1834 at Independence, Missouri, to travel to the Pacific. Along with hunters and trappers, several other scientists were on the journey to observe and bring back plant and bird specimens from the West. When they reached the Pacific, John Townsend and Thomas Nuttall collected many bird specimens, including the one that today bears his name. They then hopped a ship to the Hawaiian Islands, returned to the Pacific Northwest and, finally, Pennsylvania with crates of specimens and notes. Unfortunately, Townsend died in 1851 from arsenic that was used at the time to preserve bird skins.

In the U.S., the warbler that bears his name is found in the breeding season almost exclusively west of the Rocky Mountains in Montana, Idaho, parts of Washington and Oregon. There are similar species such as the Black-throated Green and Blackburnian, but they are found mainly in the East. Along the Oregon and Washington coasts, they can be confused with the Hermit Warbler. In fact, there is an area in which the two species have hybridized.

Here in Montana, they are easy to recognize if you can see them. These colorful warblers have dark cheek patches surrounded with yellow, a black throat, white wing bars, and extensive yellow with black stripes on their breast. The underside is primarily white.

They spend the breeding season in Montana high in the tops of conifers where they also build their cuplike nests of plant fibers, bark, moss and plant downs as high as 100 feet off the ground. They feed almost exclusively on insects and spiders. One would expect them to be quite visible with their dramatic coloration, but they are often hard to see unless sitting at the very top of the tree.

They are early arrivers in Montana, sometimes as early as late April, and they begin nesting as early as late May. When they first arrive, I have observed them in small conifers in the valley. Then they leave for higher breeding grounds such as the Big Mountain and Glacier National Park, preferring large spruce, larch, hemlock and cedar forests.

The easiest way to find these warblers is to listen for their song, which has a very distinct quality. The Peterson Field Guide to Warblers calls it “a high, raspy, wheezy, buzzy” song.” That is a good description of the quality. I say the rhythm is “zee, zee, zoo, zee.” That is a good start, but the pattern is quite variable. That quality and rhythm should work well as a starting point for identification. One thing in our favor is that there aren’t similar species in our area that have that buzzy quality.

My husband and I became very aware of their variations in song while camping at Upper Stillwater Lake late last spring. He recorded six different Townsend’s Warbler songs in a mile of hiking to Lagoni Lake. The Cornell Lab of Ornithology has good examples of the songs on their website.

Townsend’s Warblers winter on the West Coast and down to Central America. In the winter they can flock together and can be easier to see. They also winter in a small area in southeastern Arizona. In a workshop there, my husband and I encountered several people who said the Townsend’s Warbler was one of their favorite warblers because it is so easy to see. We said, “Really???” They can be seen lower in the trees foraging for insects. Their winter behavior is quite different than their breeding behavior as is the case in many migrating passerine species.

Even though I can count the times I have “seen” a Townsend’s Warbler each summer, I can’t wait to hear their buzzy song each spring and hope for a sight of this distinctive warbler.

Our Bird of the Month

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